This invention relates to the switching construction for an electronic device specially designed for increasing the reliability of the water proof characteristics of the input switch portion by the employment of electro conductive rubber for the water proof packing member.
It is possible to make a portable and handy electronic device, for example an electronic calculator, due to the remarkable development of the electronic technic especially the integrated circuit and the manufacturing technic for the display device whereby it is possible to combine the electronic calculator in a wristwatch.
It is very useful to construct the calculator and the digital electronic wristwatch in one casing as one body, however, such a combination creates new problems. Namely it is necessary to have severe water proof characteristics for the wristwatch, and it is necessary to provide many input switches for the calculator, however, it is not preferable for the water proof characteristics to provide many switches for the wristwatch, because it is necessary to provide many through holes to the casing of the wristwatch.
In the conventional type of wristwatch-calculator assembly, the water proof characteristics for sealing the switches in the wristwatch comprises a generally ring shaped rubber packing member associated with each switch. However it is not so preferable to employ said rubber packing member for said switches from the standpoint of cost and from the standpoint of overall wristwatch size. Further the reliability of the wristwatch becomes lower by the need for many water proof portions.